Arctangent Calculator

tan⁻¹(x) — find the angle whose tangent is x. Range (−90°, 90°).

Inputs

Result

tan⁻¹(1)
45.000000°
Approaches ±90° (±π/2) as |x| → ∞.
  • Result (deg)45.000000
  • Result (rad)0.785398
  • Verify: tan(result)1.000000

Step-by-step

  1. tan⁻¹(1) = 0.785398 rad = 45.000000°.

How to use this calculator

  • Enter any real number.
  • Read the angle.

About this calculator

arctan (tan⁻¹) returns the angle whose tangent is the input. Unlike arcsin/arccos, arctan accepts any real number as input. Principal range is (−90°, 90°), exclusive — never reaches the endpoints, only approaches them as |x| → ∞.

Frequently asked

Because tan(90°) is undefined. arctan approaches 90° asymptotically as input → +∞.

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